1. Field of the Invention
The present invention relates to character recognition, more particularly, it relates to character recognition using preprocessing.
2. Description of the Prior Art
Some character recognition systems use a data array to represent a character, and then use the array as an input to a neural network. U. S. Pat. No. 5,067,164 describes a recognition system that uses a pixel array as an input to a neural network. Since a character comprises many pixels, a pixel array provides a large number of inputs to the neural network. A neural network capable of receiving such a large number of inputs is complex and difficult to train. This problem is compounded when an array with several dimensions is used to include additional information describing the character. As a result, it is necessary to map several pixels into a single cell of the array, where each cell encompasses a given volume. This reduces the number of inputs to the neural network and thereby reduces the network's complexity. Unfortunately, by mapping several pixels into a cell, a quantization error is introduced. This results in a character recognition system that has unacceptable error rates and a neural network that is difficult to train.